Control device for can making machinery



y 16, 1939- v. T. GROVER 2,158,069

CONTROL DEVICE FOR CAN MAKING MACHINERY Filed Dec. 24, 1936 2Sheets-Sheet l INVENTO R lzlf g A ORN EYS' May 16, 1939. v. 'r. GROVERCONTROL DEVICE FOR CAN MAKING MACHINERY Filed Dec. 24, 1936 2Sheets-Sheet 2 INVENTOR atentecl May 16, 1939 UNITED STATES PATENTOFFICE CONTROL DEVICE FOR CAN MAKING MACHINERY Victor T. Grover,Maplewood, N. J assignor to American Can Company, New York, N. Y., acorporation of New Jersey Application December 24, 1936, Serial No.117,655

1 Claim.

The present invention relates to feed control devices for can makingmachinery and the like and has particular reference to photo-electriccontrol devices actuated by a plurality of converging beams of lightemanating from a plurality of separate and spaced sources for governingthe feeding of articles such as containers or cans passing into andthrough a runway or other conveyor.

The instant invention contemplates the use of a photo-electric controldevice for stopping the feeding of additional articles into the runwaywhen the latter becomes clogged by an accumulation of such articles andfor resuming the feeding operation when the congestion has been clearedaway.

The usual set-up of photo-electric cell illu-, minated by a beam oflight projected across the path of travel of the articles passing in therunway has been found to be insuificient for this purpose. Because ofthe keen sensitivity of the photo-electric cell the momentaryinterception of the light beam occasioned by the normal passing of anarticle through the runway is suflicient to cause actuation of thecontrol devices every time an article passes. This results in an unduejerky stopping and starting of the feeding mechanism which isundesirable for eflicient operation of the control device.

The instant invention contemplates such a control device having aplurality of light beams concentrated on a single photo-electric cell,the light beams being spaced apart so that an article passing throughthe runway will intercept them successively and as long as one or theother of the beams strike upon the photo-electric cell the latter willbe continuously illuminated sufiiciently to permit normal passage ofarticles through the runway. An accumulation of such articles, however,will intercept all of the light beams at once and cause a darkening ofthe photo-electric cell with its resultant action on the controldevices. This effects a smoother and more efiicient operation of thecontrol devices.

The invention further contemplates the projection of these light beamsat an angle across the path of travel of the articles in the runway sothat an accumulation of loosely packed articles or an accumulation ofarticles having an irregular shape will completely intercept the lightbeams and prevent illumination of the photoelectric cell. For example,where articles are to be conveyed by belt or otherwise in a horizontalplane any vibration might tend to cause momentary separation of adjacentarticles sufllciently to allow passage of light therebetween where asingle light beam is used and it is to prevent such a false conditionthat the present invention is also directed.

An object, therefore, of the invention is the provision of an electriccontrol device for governing the feeding of articles through a runway ofa can making machine or the like wherein the feeding is influenced bythe interception of a plurality of beams of light projected across thepath of travel of the articles in the runway and which normallyilluminate a single photo-electric cell unit associated with the feedcontrol devices for actuating the latter.

Another object is the provision of such a control device wherein thebeams of light are projected across the runway at an angle, convergingand concentrating on a single photo-electric cell unit disposed outsidethe runway, the beams in the runway being spaced apart so that anormally passing article will only momentarily intercept one beam at atime and thereby maintain the control devices in full article feedingoperation, while an accumulation of articles in the runway will totallyintercept all the beams at once and thereby cause cessation of feedingof additional articles until the congestion in the runway has beencleared away.

A further object is the provision in a control device of this characterwherein a plurality of spaced apart independent light sources disposedat an angle to the runway are utilized to project the converging lightbeams across the runway and to concentrate them onto a singlephotoelectric cell unit so that the beams in the runway will be properlyspaced apart for the desired interception by the articles passingtherethrough.

Numerous other objects and advantages of the invention will be apparentas it is better understood from the following description, which, takenin connection with the accompanying drawings, discloses a preferredembodiment thereof.

Referring to the drawings:

Figure l is a schematic side elevation of a pair of can making machinesconnected by conveyors one of which is equipped with electric feedcontrol devices embodying the instant invention;

Fig. 2 is a wiring diagram of the electric circuits and apparatus used;

Fig. 3 is an enlarged transverse sectional view of the control devicesshowing one arrangement of photo-electric cell unit and light source,the view being taken substantially along the line 33 of Fig. 1; and

Figs. 4, 5 and 6 are horizontal sections taken substantially along thebroken line 44 in Fig. 3, Fig. 4 showing the normal passage of articlesthrough the conveyor and through the light beams of the control devices;Fig. 5 illustrating articles in the conveyor accumulated to the extentof blocking off one of the light beams with the other beam stillilluminating the photo-electric cell to maintain feeding of thearticles, and Fig. 6 shows the limit of such an article accumulation inthe conveyor, the accumulated articles blocking off both light beamsfrom the photo-electric cell and causing a temporary cessation offurther feeding of articles.

As a preferred embodiment of the instant invention the drawingsillustrate a container making machine II (diagrammatically shown inFig. 1) and a contiguous belt conveyor I2 which will be hereinaftercollectively referred to as the article feeding mechanism. Thismechanism is preferably used for performing an operation on containers Aor the like articles and for delivering or feeding them forward to asubsequent operation machine I3 (also diagrammatically shown in Fig. l).The feeding mechanism is preferably actuated by an electric motor I4.

Containers delivered by the feeding mechanism are preferably raised to aposition over the top of the subsequent operation machine I3. For thispurpose the belt conveyor I2 is partly inclined. The conveyor is drivenby a driving pulley I5 which forms a part of the feeding mechanism andis indirectly driven by the motor I4. The upper run of the belt takesover a pair of idler pulleys I6, IT. The lower run takes over aplurality of idler pulleys I8.

The belt conveyor I2 preferably drops the containers into a verticalrunway I9 the upper end of which is located in alignment with theconveyor adjacent the idler pulley IT. The lower end of the runwayconnects with the receiving machine I3. Containers deposited in therunway fall by gravity and are guided by the runway into the receivingmachine. For this purpose the runway is formed with oppositely disposedchannel shaped side members 2I (Figs. 3, l, 5 and 6).

Provision is made for controlling the feeding of the containers from thefeeding mechanism to prevent clogging of the runway I9 under adverseoperating conditions which may prevail at times in the receivingmachine. This feeding is controlled by electric devices which include aphotoelectric cell unit located adjacent the runway. A photo-electriccell 25 (Figs. 3, 4, 5 and 6) is disposed on one side of the runwayadjacent one of the members 2I and is secured to a bracket 26 which isbolted to the flanges of the members.

On the opposite side of the runway I9 the bracket 26 carries a pair oflamps 2'! which constitute sources of light for projecting restrictedbeams of light 28 into the photo-electric cell 25. The lamps are spacedapart and are set at an angle so that the light beams pass obliquelythrough the runway across the path of travel of the containers and arefocused to concentrate on the photo-electric cell as shown in Fig. 4.Windows 29, 3I secured in the sides of the runway members 2I permit thelight beams to pass across the runway.

The spacing of the lamps and the angle at which they are set is arrangedso that a container A falling in the runway will pass successively thelight beams without blocking off both of them simultaneously. Thisinsures that when the passing container normally blocks off one beam theother will still illuminate the photo-electric cell to keep it inoperation. Should more than two light beams be used, each will bearranged so that all light passing into the photo-electric cell will beblocked off only when there is an accumulation. of articles.

Referring now to the wiring diagram in Fig. 2 it will be observed thatthe photo-electric cell unit 25 is connected by wires 32, 33 to aphotoelectric amplifying relay indicated by the numeral 35. The lamps 21are connected to the relay by wires 36, 31 and a solenoid 38 is alsoconnected to the relay by wires 39, 4I. Electric energy is supplied tothe relay and the parts associated therewith in any suitable manner asby lead wires 42, 43and a service switch 44 which connect with a sourceof power such as a generator 45.

The amplifying relay 35 is in itself a well known commercial article andprovides for energizing and de-energizing the solenoid 38 through theaction of the photo-electriccell 25 when the latter is illuminated ordarkened. In the present use of the relay the solenoid is de-energizedwhen the photo-electric cell is darkened and the resulting action isutilized to stop the feeding of articles into the runway I9.

In the form herein illustrated the solenoid 38 is utilized to controlthe operation of the electric motor I4 of the feeding mechanism. Thesolenoid opens and closes a switch 46 which is included in a motorcircuit receiving electric energy from a suitable source of power suchas a generator 41. The switch is connected by a wire 48 to one terminalof the motor and by a wire 49 to a service switch 5I used for manuallystarting and stopping the motor. The service switch is connected bywires 52, 53 to the generator 41 and also by a wire 54 to the motor I4thus making a'complete circuit when the switches are closed.

During normal operation of the feeding mechanism falling containersmoving through-the runway I9 and successively passing the light beams 28of the control device have no effect on the relay 35 since one of thelight beams continues to strike the photo-electric cell 25 when afalling container passes the other beam. Therefore the photo-electriccell is normally kept illuminated and the energized solenoid 38continues to hold the switch 46 closed. The motor circuit is thusmaintained, the service switch 5I being closed and the flow of electricenergy from the generator 4'! therefore continues to rotate the motor I4which in its turn causes the feeding mechanism to deliver containersinto the runway I9.

When for any reason the feeding mechanism delivers the containers fasterthan they can be operated upon in the receiving machine they accumulatein the runway I9 as shown in Figs, 5 and 6. When accumulated containersreach a height where they block ofi both beams of light 28 coming fromthe lamps 21 as shown in Fig. 6 the resulting darkened photo-electriccell 25 acts on the relay 35 to de-energize the solenoid 38. This opensthe switch 46, breaks the motor circuit and stops the operation of thefeeding mechmechanism to feed more containers into the runway. Thus thefeeding of containers or the stopping of the feed is continually andautomatically efiected or resumed to prevent clogging of the runway.

It is thought that the invention and many of its attendant advantageswill be understood from the foregoing description, and it will beapparent that various changes may be made in the form, construction andarrangement of the parts without departing from the spirit and scope ofthe invention or sacrificing all of its material advantages, the formhereinbefore described being merely a preferred embodiment thereof.

I claim:

A feed control device for container parts comprising in combination: arunway, a photo-electric cell unit disposed adjacent the path of movingparts in said runway, said unit including a photo-electric cell disposedon one side of said runway and a plurality of light beams from spacedlight sources disposed on the opposite side of said runway, said lightbeams projecting obliquely across said runway and converging onto saidcell, the space between said light beams across said runway beinggreater than the width of a said container part, whereby normal feed ofsaid parts in spaced relation along said runway through said light beamscannot temporarily intercept more than one light beam simultaneouslythereby failing to darken said cell, abnormal accumulation of saidcontainer parts in the runway adjacent said units serving tosimultaneously intercept all of said light beams to thereby temporarilydarken said cell until the abnormal accumulation of parts is relieved,and electrical means responsive to the condition of said cell forterminating the feed of said parts when said cell is darkened underabnormal conditions, said electrical means being further operable toreestablish and permit the feed of said parts under normal conditionswhen one or more of said light beams are projected upon said cell.

VICTOR T. GROVER.

